Irish-based scientists develop 'sponge' for emissions by accident

Calling it “a glorious failure” of sorts, UL scientists’ latest discovery came about by accident, with an investigation into ’sieving’ out polluting gases producing something far more effective. The UL team, led by Professor Michael Zaworotko and Dr Kai-Jie Chen, was looking at ways to filter out acetylene, a colourless gas, made up of carbon and hydrogen, using a sieve-like structure called SIFSIX-2-Cu-i.

Through their investigations, though, they found that the structure actually operates like a sponge, capable of soaking up acetylene during the production of ethylene, which proved a far more successful option to manage the gases. “In a way this was a glorious failure,” said Zaworotko, “where the outcome was so much better than expected.”

Plastic fantastic

The chemical name for the plastic you see every day – in water bottles, grocery bags and household appliances – is polyethylene, a pliable material made by stringing together long chains of a simpler molecule called ethylene. Worldwide demand for plastic makes ethylene the most widely-produced organic compound in the world, with more than 100m tonnes of it manufactured each year, largely by refining crude oil.

Ethylene is used to ripen fruit or make plastics such as polythene, however, acetylene impurities are costly to remove during the process. That’s because the options available are distillation – energy-sapping – or purification – which doesn’t work at the end stage.

The team says their new invention offers a more environmentally-friendly, cost-effective way to purify ethylene.

Other purification uses, too

But it’s not just ethylene production that can benefit, should this discovery roll out into regular use. The same approaches could also work for purification of other substances like carbon and water, according to the scientists, who published their paper in Science.

Should that prove correct, major savings are on the way. As commodity purification currently uses a lot of energy, if new approaches like this were successful it could dramatically reduce both carbon dioxide emission and the energy costs associated with it, according to the team.

UL’s Prof Edmond Magner said this SFI-backed research is a “prime example” of how his institution’s investigations can help industry.